Abstract
Over
80% of all chronic bacterial infections in humans are associated with biofilms,
which are surface-associated bacterial communities encased within a secreted
exopolysaccharide matrix that can provide resistance to environmental and
chemical insults. Biofilm formation triggers broad adaptive changes in the
bacteria, allowing them to be almost a thousand-fold more resistant to
conventional antibiotic treatments and host immune responses. The failure of
antibiotics to eliminate biofilms leads to persistent chronic infections and
can promote the development of antibiotic-resistant strains. Therefore, there
is an urgent need to develop agents that effectively prevent biofilm formation
and eradicate established biofilms. Herein, we present water-soluble synthetic
peptidomimetic polyurethanes that can disrupt surface established biofilms of Pseudomonas
aeruginosa, Staphylococcus aureus, and Escherichia coli, all of
which show tolerance to the conventional antibiotics polymyxin B and ciprofloxacin.
Furthermore, these polyurethanes prevent bacterial attachment and stimulate
bacterial surface motility to inhibit biofilm formation of both Gram-positive
and Gram-negative bacteria at sub-inhibitory concentrations, without being
toxic to mammalian cells. Our results show that these polyurethanes show
promise as a platform for the development of therapeutics that target biofilms
and modulate surface interactions of bacteria for the treatment of chronic
biofilm-associated infections and as antibiofilm agents.